Obeticholic acid reduces biliary and hepatic matrix metalloproteinases activity in rat hepatic ischemia/reperfusion injury

Edaravone and obeticholic acid protect against cisplatin-induced heart toxicity by suppressing oxidative stress and inflammation and modulating Nrf2, TLR4/p38MAPK, and JAK1/STAT3/NF-κB signals

Cardiotoxicity is a significant adverse effect of cisplatin (CIS) that necessitates extensive medical care. The current study examines the cardioprotective effects of edaravone (EDV), obeticholic acid (OCA), and their combinations on CIS-induced cardiac damage. Rats were allocated into five groups: the normal control group, the remaining four groups received CIS (7.5 mg/kg, i.p.) as a single dose on the fifth day and were assigned to CIS, OCA (10 mg/kg/day) + CIS, EDV (20 mg/kg/day) + CIS, and the (EDV + OCA) + CIS group. Compared to the CIS-treated group, co-treating rats with EDV, OCA, or their combinations significantly decreased ALP, AST, LDH, CK-MB, and troponin-I serum levels and alleviated histopathological heart abnormalities. Biochemically, EDV, OCA, and EDV plus OCA administration mitigated cardiac oxidative stress as indicated by a marked decrease in heart MDA content with a rise in cardiac antioxidants SOD and GSH associated with upregulating Nrf2, PPARγ, and SIRT1 expression. Besides, it dampened inflammation by decreasing cardiac levels of TNF-α, IL-1β, and IL-6, mediated by suppressing NF-κB, JAK1/STAT3, and TLR4/p38MAPK signal activation. Notably, rats co-administered with EDV plus OCA showed noticeable protection that exceeded that of EDV and OCA alone. In conclusion, our study provided that EDV, OCA, and their combinations effectively attenuated CIS-induced cardiac intoxication by activating Nrf2, PPARγ, and SIRT1 signals and downregulating NF-κB, JAK1/STAT3, and TLR4/p38MAPK signals.

FXR agonists INT-787 and OCA increase RECK and inhibit liver steatosis and inflammation in diet-induced ob/ob mouse model of NASH

BACKGROUND AND AIMS

We have previously shown in a model of hepatic ischaemia/reperfusion injury that the farnesoid X receptor (FXR) agonist obeticholic acid (OCA) restores reversion-inducing-cysteine-rich protein with Kazal motifs (RECK), an inverse modulator of metalloproteases (MMPs) and inhibitor of the sheddases ADAM10 and ADAM17 involved in inflammation and fibrogenesis. Here, the effects of FXR agonists OCA and INT-787 on hepatic levels of RECK, MMPs, ADAM10 and ADAM17 were compared in a diet-induced ob/ob mouse model of non-alcoholic steatohepatitis (NASH).

METHODS

Lep ob/ob NASH mice fed a high-fat diet (HFD) or control diet (CD) for 9 weeks (wks) were treated with OCA or INT-787 0.05% dosed via HFD admixture (30 mg/kg/day) or HFD for further 12 wks. Serum alanine transaminase (ALT) and inflammatory cytokines, liver RECK, MMP-2 and MMP-9 activity as well as ADAM10, ADAM17, collagen deposition (Sirius red), hepatic stellate cell activation (α-SMA) and pCK+ reactive biliary cells were quantified.

RESULTS

Only INT-787 significantly reduced serum ALT, IL-1β and TGF-β. A downregulation of RECK expression and protein levels observed in HFD groups (at 9 and 21 wks) was counteracted by both OCA and INT-787. HFD induced a significant increase in liver MMP-2 and MMP-9; OCA administration reduced both MMP-2 and MMP-9 while INT-787 markedly reduced MMP-2 expression. OCA and INT-787 reduced both ADAM10 and ADAM17 expression and number of pCK+ cells. INT-787 was superior to OCA in decreasing collagen deposition and α-SMA levels.

CONCLUSION

INT-787 is superior to OCA in controlling specific cell types and clinically relevant anti-inflammatory and antifibrotic molecular mechanisms in NASH.

Recent Updates on the Therapeutic Prospects of Reversion-Inducing Cysteine-Rich Protein with Kazal Motifs (RECK) in Liver Injuries

The reversion-inducing cysteine-rich protein with Kazal motifs (RECK), a membrane-anchored glycoprotein, negatively regulates various membrane proteins involved in the tissue governing extracellular matrix (ECM) remodeling such as metalloproteases (MMPs) and the sheddases ADAM10 and ADAM17. The significance of the present review is to summarize the current understanding of the pathophysiological role of RECK, a newly discovered signaling pathway associated with different liver injuries. Specifically, this review analyzes published data on the downregulation of RECK expression in hepatic ischemia/reperfusion (I/R) injury, liver-related cancers, including hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), as well as in the progression of nonalcoholic fatty liver disease (NAFLD) to non-alcoholic steatohepatitis (NASH). In addition, this review discusses the regulation of RECK by inducers, such as FXR agonists. The RECK protein has also been suggested as a potential diagnostic and prognostic marker for liver injury or as a biomarker with predictive value for drug treatment efficacy.

Novel Approaches for Targeting Metalloproteinases

With 187 genes, metalloproteinases represent the most abundant protease family in the human proteome [...].

Fatty Acids and Bilirubin as Intrinsic Autofluorescence Serum Biomarkers of Drug Action in a Rat Model of Liver Ischemia and Reperfusion

The autofluorescence of specific fatty acids, retinoids, and bilirubin in crude serum can reflect changes in liver functional engagement in maintaining systemic metabolic homeostasis. The role of these fluorophores as intrinsic biomarkers of pharmacological actions has been investigated here in rats administered with obeticholic acid (OCA), a Farnesoid-X Receptor (FXR) agonist, proven to counteract the increase of serum bilirubin in hepatic ischemia/reperfusion (I/R) injury. Fluorescence spectroscopy has been applied to an assay serum collected from rats submitted to liver I/R (60/60 min ± OCA administration). The I/R group showed changes in the amplitude and profiles of emission spectra excited at 310 or 366 nm, indicating remarkable alterations in the retinoid and fluorescing fatty acid balance, with a particular increase in arachidonic acid. The I/R group also showed an increase in bilirubin AF, detected in the excitation spectra recorded at 570 nm. OCA greatly reversed the effects observed in the I/R group, confirmed by the biochemical analysis of bilirubin and fatty acids. These results are consistent with a relationship between OCA anti-inflammatory effects and the acknowledged roles of fatty acids as precursors of signaling agents mediating damaging responses to harmful stimuli, supporting serum autofluorescence analysis as a possible direct, real-time, cost-effective tool for pharmacological investigations.

Effects of iNOS in Hepatic Warm Ischaemia and Reperfusion Models in Mice and Rats: A Systematic Review and Meta-Analysis

Warm ischaemia is usually induced by the Pringle manoeuver (PM) during hepatectomy. Currently, there is no widely accepted standard protocol to minimise ischaemia-related injury, so reducing ischaemia-reperfusion damage is an active area of research. This systematic review and meta-analysis focused on inducible nitric oxide synthase (iNOS) as an early inflammatory response to hepatic ischaemia reperfusion injury (HIRI) in mouse- and rat-liver models. A systematic search of studies was performed within three databases. Studies meeting the inclusion criteria were subjected to qualitative and quantitative synthesis of results. We performed a meta-analysis of studies grouped by different HIRI models and ischaemia times. Additionally, we investigated a possible correlation of endothelial nitric oxide synthase (eNOS) and nitric oxide (NO) regulation with iNOS expression. Of 124 included studies, 49 were eligible for the meta-analysis, revealing that iNOS was upregulated in almost all HIRIs. We were able to show an increase of iNOS regardless of ischemia or reperfusion time. Additionally, we found no direct associations of eNOS or NO with iNOS. A sex gap of primarily male experimental animals used was observed, leading to a higher risk of outcomes not being translatable to humans of all sexes.

MCD Diet Rat Model Induces Alterations in Zinc and Iron during NAFLD Progression from Steatosis to Steatohepatitis

We evaluate the effects of the methionine-choline-deficient (MCD) diet on serum and hepatic zinc (Zn) and iron (Fe) and their relationships with matrix metalloproteinases (MMPs) and their modulators (TIMPs and RECK) as well as hepatic fatty acids using male Wistar rats fed 2-, 4- and 8-week MCD diets. Serum and hepatic Zn decrease after an 8-week MCD diet. Serum Fe increases after an 8-week MCD diet and the same occurs for hepatic Fe. An increase in hepatic MMP activity, associated with a decrease in RECK and TIMPs, is found in the MCD 8-week group. Liver Fe shows a positive correlation versus MMPs and RECK, and an inverse correlation versus TIMPs. A positive correlation is found comparing liver Zn with stearic, vaccenic and arachidonic acids, and an inverse correlation is found with linolenic and docosatetraenoic acids. An opposite trend is found between liver Fe versus these fatty acids. During NAFLD progression from steatosis to steatohepatitis, MCD rats exhibit an increase in Zn and a decrease in Fe levels both in serum and tissue associated with alterations in hepatic MMPs and their inhibitors, and fatty acids. The correlations detected between Zn and Fe versus extracellular matrix modulators and fatty acids support their potential role as therapeutic targets.

Obeticholic Acid Reduces Kidney Matrix Metalloproteinase Activation following Partial Hepatic Ischemia/Reperfusion Injury in Rats

We have previously demonstrated that the farnesoid X receptor (FXR) agonist obeticholic acid (OCA) protects the liver via downregulation of hepatic matrix metalloproteinases (MMPs) after ischemia/reperfusion (I/R), which can lead to multiorgan dysfunction. The present study investigated the capacity of OCA to modulate MMPs in distant organs such as the kidney. Male Wistar rats were dosed orally with 10 mg/kg/day of OCA (5 days) and were subjected to 60-min partial hepatic ischemia. After 120-min reperfusion, kidney biopsies (cortex and medulla) and blood samples were collected. Serum creatinine, kidney MMP-2, and MMP-9-dimer, tissue inhibitors of MMPs (TIMP-1, TIMP-2), RECK, TNF-alpha, and IL-6 were monitored. MMP-9-dimer activity in the kidney cortex and medulla increased after hepatic I/R and a reduction was detected in OCA-treated I/R rats. Although not significantly, MMP-2 activity decreased in the cortex of OCA-treated I/R rats. TIMPs and RECK levels showed no significant differences among all groups considered. Serum creatinine increased after I/R and a reduction was detected in OCA-treated I/R rats. The same trend occurred for tissue TNF-alpha and IL-6. Although the underlying mechanisms need further investigation, this is the first study showing, in the kidney, beneficial effects of OCA by reducing TNF-alpha-mediated expression of MMPs after liver I/R.

Protective Effect of Liposomal Epigallocatechin-Gallate in Experimental Gentamicin-Induced Hepatotoxicity

Our study aimed to assess the effect of liposomal epigallocatechin-gallate (LEGCG) compared with epigallocatechin-gallate (EGCG) solution on hepatic toxicity induced by gentamicin (G) administration in rats. Five groups were evaluated, a control group (no G administration) and four groups that received G (1 mL, i.p, 80 mg/kg b.w. (body weight/day), for 7 days) to which we associated daily administration 30 min before G of EGCG (G-EGCG, 2.5 mg/0.1 kg b.w.), LEGCG (G-LEGCG, 2.5 mg/0.1 kg b.w.) or silymarin (100 mg/kg b.w./day). The nitro-oxidative stress (NOx), catalase (CAT), TNF-α, transaminases, creatinine, urea, metalloproteinase (MMP) 2 and 9, and liver histopathological changes were evaluated. LEGCG exhibited better efficacy than EGCG, improving the oxidant/antioxidant balance (p = 0.0125 for NOx and 0.0032 for CAT), TNF-α (p < 0.0001), MMP-2 (p < 0.0001), aminotransferases (p = 0.0001 for AST and 0.0136 for ALT), creatinine (p < 0.0001), urea (p = 0.0006) and histopathologic liver changes induced by gentamicin. Our study demonstrated the beneficial effect of EGCG with superior results of the liposomal formulation for hepatoprotection in experimental hepatic toxicity induced by gentamicin.

Protective Effect of Liposomal Epigallocatechin-Gallate in Experimental Gentamicin-Induced Hepatotoxicity

Our study aimed to assess the effect of liposomal epigallocatechin-gallate (LEGCG) compared with epigallocatechin-gallate (EGCG) solution on hepatic toxicity induced by gentamicin (G) administration in rats. Five groups were evaluated, a control group (no G administration) and four groups that received G (1 mL, i.p, 80 mg/kg b.w. (body weight/day), for 7 days) to which we associated daily administration 30 min before G of EGCG (G-EGCG, 2.5 mg/0.1 kg b.w.), LEGCG (G-LEGCG, 2.5 mg/0.1 kg b.w.) or silymarin (100 mg/kg b.w./day). The nitro-oxidative stress (NOx), catalase (CAT), TNF-α, transaminases, creatinine, urea, metalloproteinase (MMP) 2 and 9, and liver histopathological changes were evaluated. LEGCG exhibited better efficacy than EGCG, improving the oxidant/antioxidant balance (p = 0.0125 for NOx and 0.0032 for CAT), TNF-α (p < 0.0001), MMP-2 (p < 0.0001), aminotransferases (p = 0.0001 for AST and 0.0136 for ALT), creatinine (p < 0.0001), urea (p = 0.0006) and histopathologic liver changes induced by gentamicin. Our study demonstrated the beneficial effect of EGCG with superior results of the liposomal formulation for hepatoprotection in experimental hepatic toxicity induced by gentamicin.

Protective Effect of Liposomal Epigallocatechin-Gallate in Experimental Gentamicin-Induced Hepatotoxicity

Our study aimed to assess the effect of liposomal epigallocatechin-gallate (LEGCG) compared with epigallocatechin-gallate (EGCG) solution on hepatic toxicity induced by gentamicin (G) administration in rats. Five groups were evaluated, a control group (no G administration) and four groups that received G (1 mL, i.p, 80 mg/kg b.w. (body weight/day), for 7 days) to which we associated daily administration 30 min before G of EGCG (G-EGCG, 2.5 mg/0.1 kg b.w.), LEGCG (G-LEGCG, 2.5 mg/0.1 kg b.w.) or silymarin (100 mg/kg b.w./day). The nitro-oxidative stress (NOx), catalase (CAT), TNF-α, transaminases, creatinine, urea, metalloproteinase (MMP) 2 and 9, and liver histopathological changes were evaluated. LEGCG exhibited better efficacy than EGCG, improving the oxidant/antioxidant balance (p = 0.0125 for NOx and 0.0032 for CAT), TNF-α (p < 0.0001), MMP-2 (p < 0.0001), aminotransferases (p = 0.0001 for AST and 0.0136 for ALT), creatinine (p < 0.0001), urea (p = 0.0006) and histopathologic liver changes induced by gentamicin. Our study demonstrated the beneficial effect of EGCG with superior results of the liposomal formulation for hepatoprotection in experimental hepatic toxicity induced by gentamicin.